Mixing cooking oils?

I am going to attempt to fry a turkey tomorrow, and I bought a 3 gallon jug of peanut oil. After doing the water test, I dont think that is going to be enough oil, and I cant find any more peanut oil anywhere. However, there is plenty of conola oil on the store shelves. I only need about half a gallon, and was wondering if it is safe to top off the peanut oil with some conola oil. If it is safe, will it adversely affect the taste?